L(-)-Proline

L(-)-Proline - Names and Identifiers

Name	L(-)-Proline
Synonyms	Proline H-Pro-OH L-Proline L(-)-Proline L(-)-Proline 0 L-PROLINE, NATURAL L-PROLINE, SYNTHETIC 2-Pyrrolidinecarboxylic acid L-(-)-PROLINE ((S)-(-)-PROLINE) (S)-Pyrrolidine-2-carboxylic acid L-Proline ,L-2-Pyrrolidinecarboxylic acid
CAS	147-85-3
EINECS	205-702-2
InChI	InChI=1/C5H9NO2/c7-5(8)4-2-1-3-6-4/h4,6H,1-3H2,(H,7,8)/t4-/m1/s1
InChIKey	ONIBWKKTOPOVIA-UHFFFAOYSA-N

L(-)-Proline - Physico-chemical Properties

Molecular Formula	C5H9NO2
Molar Mass	115.13
Density	1.35
Melting Point	228 °C (dec.) (lit.)
Boling Point	215.41°C (rough estimate)
Specific Rotation(α)	-85.5 º (c=4, H2O)
Flash Point	106.3°C
JECFA Number	1425
Water Solubility	soluble
Solubility	Soluble in water and ethanol, insoluble in ether, butanol and isopropanol, soluble in inorganic acid. Solubility in water: 1623g/L (25°C), ethanol solubility: 67g/100mL (19°C).
Vapor Presure	0Pa at 25℃
Appearance	Crystallization
Color	White
Maximum wavelength(λmax)	['λ: 260 nm Amax: 0.05', , 'λ: 280 nm Amax: 0.05']
Merck	14,7780
BRN	80810
pKa	1.95, 10.64(at 25℃)
PH	6.0-7.0 (25℃, 1M in H2O)
Storage Condition	2-8°C
Stability	Stable. Incompatible with strong oxidizing agents.
Sensitive	Hygroscopic
Refractive Index	-85 ° (C=4, H2O)
MDL	MFCD00064318
Physical and Chemical Properties	density 1.35 melting point 228-233°C specific optical rotation -85.5 ° (c = 4, H2O) water-soluble solution
Use	Used for amino acid injection, compound amino acid infusion, food additives, nutrition supplement

L(-)-Proline - Risk and Safety

Risk Codes	R36/37/38 - Irritating to eyes, respiratory system and skin. R22 - Harmful if swallowed
Safety Description	S24/25 - Avoid contact with skin and eyes. S36/37/39 - Wear suitable protective clothing, gloves and eye/face protection. S26 - In case of contact with eyes, rinse immediately with plenty of water and seek medical advice.
WGK Germany	3
RTECS	TW3584000
FLUKA BRAND F CODES	3-10
TSCA	Yes
HS Code	29339990
Toxicity	LD50 orally in Rabbit: > 5110 mg/kg

L(-)-Proline - Upstream Downstream Industry

Raw Materials	Dextrose Anhydrate
Downstream Products	D-Proline captopril lisinopril Enalapril

L(-)-Proline - Nature

Open Data Verified Data

This product is needle-like crystal or orthorhombic crystal. There is a strong sweet taste, almost odorless. Melting Point 222 °c (decomposition). Very soluble in water (162. 3%,25 ℃), soluble in ethanol, insoluble in ether and butanol, easy deliquescence, not easy to get crystallization.
It is a pyrrolidine-containing imino acid and is one of the non-essential amino acids. In the living body, it is synthesized from glutamic acid by Δ' pyrroline-5-carboxylic acid, and the decomposition is transferred to glutamic acid metabolism through the same process as the reverse reaction of biosynthesis. In proteins such as collagen, the amino acid residues are present in hydroxylated form (hydroxyproline).

Last Update：2024-01-02 23:10:35

L(-)-Proline - Hair-making

Open Data Verified Data

chemical method.
direct fermentation method.

Last Update：2022-01-01 11:10:30

L(-)-Proline - Use

Open Data Verified Data

amino acid drugs. It is one of the raw materials for compound amino acid infusion. Protein Supplementation for malnutrition, protein deficiency, severe gastrointestinal disorders, Burns and after surgery.

Last Update：2022-01-01 11:10:30

L(-)-Proline - Safety

Open Data Verified Data

sealed storage.

Last Update：2022-01-01 11:10:30

L(-)-Proline - Reference Information

FEMA	3319 \| L-PROLINE
LogP	-2.54 at 20℃
NIST chemical information	Information provided by: webbook.nist.gov (external link)
EPA chemical information	Information provided by: ofmpub.epa.gov (external link)
Eighteen amino acids for human protein synthesis	L-proline (proline for short) is one of the eighteen amino acids for human protein synthesis. It is colorless to white crystal or crystalline powder at room temperature, slightly smelly, slightly sweet, easily soluble in water, insoluble in ethanol, insoluble in ether and n-butanol. Amino acid is a general term for a class of organic compounds containing amino and carboxyl groups. The presence of amino acids in the human body not only provides an important raw material for protein synthesis, but also provides a material basis for promoting growth, normal metabolism, and maintaining life. The main uses of L-proline are as follows: 1. As an amino acid, it can supplement nutrients and is the raw material for amino acid infusion. 2, it has curative effect on hypertension and is an important intermediate for synthesizing captopril, enalapril and other first-line antihypertensive drugs. 3,L-proline and sugar co-heat amino acid-carboxyl reaction, can produce a special fragrance of substances. 4, as a nutritional supplement, it can improve tissue resistance and increase the survival rate of callus. 5, can effectively alleviate the damage of salt stress to the mitochondrial structure of rice regenerated plants.
identification test	add 1 ml of ninhydrin hydrate test solution (TS-250) to 5ml of 0.1% sample solution, and yellow should appear.
content analysis	accurately weigh about 220mg of the sample pre-dried at 105 ℃ for 3h, dissolve in 3ml of formic acid and 50ml of glacial acetic acid, add 2 drops of crystal violet test solution (TS-74), and titrate with 0.1mol/L perchloric acid to the blue-green endpoint. 0.1mol/L perchloric acid per Ml is equivalent to L-proline (C5 H9NO2)11.51mg.
toxicity	can be safely used in food (FDA, 172?320,2000).
use limit	4.2% of total protein mass in food (FDA,§ 172.320,2000)FEMA: same as "01029, thiamine hydrochloride".
use	used for biochemical research, medicine for malnutrition, protein deficiency, gastrointestinal diseases, burns and postoperative protein supplement, etc. Amino acid drugs. It is one of the raw materials of compound amino acid infusion, which is used for protein supplement after malnutrition, protein deficiency, severe gastrointestinal diseases, burns and surgical operations. Nutritional supplements. Flavor, co-heat with sugar to produce amino-carbonyl reaction, can produce special fragrance substances. It can be used as a spice according to our GB 2760-86. Pharmaceutical raw materials and food additives. Used for biochemical research, medically used for malnutrition, protein deficiency, gastrointestinal diseases, burns and postoperative protein supplementation. Amino acid drugs. It is one of the raw materials of compound amino acid infusion, which is used for protein supplement after malnutrition, protein deficiency, severe gastrointestinal diseases, burns and surgical operations. Nutritional supplements. Flavor, co-heat with sugar to produce amino-carbonyl reaction, can produce special fragrance substances. It can be used as a spice according to our GB 2760-86. Used for amino acid injection, compound amino acid infusion, food additives, nutritional supplements and other pharmaceutical raw materials and food additives. Nutritional supplements. Flavor. Amino acid-carbonyl reaction occurs in co-heating with sugar, which can produce special fragrance substances
production method	hydrolysates of proteins such as gelatin and casein are treated with ion exchange resin, and then the neutral amino acid part is treated with picric acid or reynkert salt (Reineckeatesalt), only L-proline is precipitated, and finally recrystallized with absolute ethanol and isopropanol. It was XQ-3 by Corynebacterium acetoacetate (Corynebacteriumacetoacidophilum) (selected by the Central Research Institute of Wuxi University of Light Industry) and fermented with ammonium chloride as a nitrogen source. The acid production rate is about 60g/L. There are two preparation methods for L-proline. One is the direct fermentation method, using glucose and Brevibacterium yellow variant or Corynebacterium glutamicum wild strain, through microbial fermentation to obtain L-proline; the other is the chemical synthesis method, using glutamic acid as the raw material, and anhydrous Ethanol undergoes esterification under the catalysis of sulfuric acid, and triethanolamine is added to free the amino sulfate to obtain glutamic acid-δ-ethyl ester. Then use the metal reducing agent potassium borohydride to reduce glutamic acid-δ-ethyl ester to obtain crude proline, and finally separate and purify it to obtain crude proline. In the small test process, 147g of L-glutamic acid was weighed by esterification, put into a three-neck bottle, 1L of absolute ethanol was added, stirred and cooled to 0 ℃, then 80ml of H2SO4 was added dropwise, stirred and reacted at 0-5 ℃ for 1h, and the reaction was continued for 1h at room temperature, and the reaction was completely clear. Triethylamine was added dropwise at 20 ℃ until pH was 8-8.5, white crystals were precipitated, stirred at room temperature for another 1h, let stand and cool at 5 ℃ for filtration, take the crystals, wash with 95% ethanol, dry and vacuum dry to obtain about 141g of glutamic acid-δ-ethyl ester. Melting point 178-180 ℃, yield 80%-83%. [α]32D +29.8 (C = 1 g/ml 10% HCl). Reduction: 175g of glutamic acid-δ-ethyl ester is added into a three-neck bottle, 875ml of distilled water is added, stirred and cooled to 5 ℃, then 53.9g of KBH4 is added in several times, the addition is completed for about 1h, the reaction is carried out at room temperature for 1h, and the reaction is carried out at 50 ℃ for 3h. Cooling to 0 ℃, adding 6mol/L HCl to pH4, filtering to obtain the filtrate to obtain crude L-proline aqueous solution. Separation and Purification Ion Exchange Resin-Alumina Column Chromatographic Separation Method The crude L-proline aqueous solution was put into a 732-H + type resin exchange column at a flow rate of 4ml/min (10ml resin is required for 1g of acid feed). Rinse with distilled water to neutral, then elute with 1mol/L ammonia water, and collect the eluent containing L-proline segment (controlled by silica gel G thin layer chromatography). The eluent is concentrated to dryness under reduced pressure, dissolved in a small amount of water, then entered into a neutral alumina column, and then eluted with 60% ethanol aqueous solution (or controlled by silica gel G thin layer chromatography). The collected eluent is concentrated to dry under reduced pressure, washed several times with absolute ethanol, added with anhydrous ether after a little cooling, cooled and filtered to crystallize, and dried in vacuum to obtain L-proline. Melting point 220-222 ℃ (decomposition), yield about 28%. [α]24D-82.4 (C = 1 g/ml, H2O). Pentachlorophenol precipitation desorption separation method to form salt Place the crude proline aqueous solution in a reaction flask, add pentachlorophenol ethanol solution (0.111mol/70ml ethanol) dropwise when heated to 50 ℃, keep the temperature and stir for 5 hours, let cool to 0 ℃, filter to take crystallization, wash with a small amount of ice water, drain, dry, and dry to obtain compound salt after drying, with melting point 240-242 ℃, and precipitation rate 95%. Analysis: 38.4g of double salt is put into a three-neck bottle, 200ml of distilled water and 20ml of ammonia water are added, stirred at room temperature for 8 hours, cooled to 0 ℃, filtered to take filtrate, concentrated filtrate under reduced pressure, 100ml of distilled water is added, filtered to take filtrate, and activated carbon is added to decolorize. Ether extraction, separation of water layer, continue to concentrate to dry, decolorize with anhydrous ethanol several times, add a small amount of anhydrous ethanol to moisten, add 2 times the amount of anhydrous ether, cool and crystallize, filter to crystallize, vacuum dry to obtain L-Proline finished product. Enlarged production process esterification: 15kg of L-glutamic acid and 100L of anhydrous ethanol are put into a 200L reaction tank, cooled to 0 ℃, concentrated H2SO4 8.1L is added dropwise under stirring conditions, kept at 0 ℃, stirred for 1h, heated at 25 ℃ for stirring for 1h, and triethylamine is added to make the pH 8.0-8.5. Stir for 1h, white precipitate appears. Cool to 5 ℃, filter to take precipitate, wash with 50L 95% ethanol, and dry the precipitate in vacuum at 50 ℃ to obtain L-glutamic acid-δ-ethyl ester. Reduction: Put the obtained L-glutamic acid-δ-ethyl ester into a 100L reaction tank, add 70L of water, stir and cool to 5 ℃, add 4.3kg KBH4 in batches within 1h, heat and keep the temperature at 200 ℃, stir and react for 1h, raise the temperature at 50 ℃, stir and react for 3-4h, cool to 0 ℃, adjust the pH to 4.0 with 6mol/L HCl, and filter the filtrate to obtain L-proline crude solution. Precipitation: Put the crude L-proline solution into a 100L reaction tank, heat to 50 ℃, slowly add 7L 1.5mol/L pentachlorophenol ethanol solution under continuous stirring, keep the temperature at 50 ℃ for 5 hours, cool to 0 ℃ to precipitate crystallization, filter to take crystallization, drain to obtain compound salt. Analysis and Refining Put the double salt into a 100L reaction tank, add 20L of 3% ammonia water, stir for 7-8h at room temperature, cool to 0 ℃ for filtration, wash the precipitate with a small amount of ice water, drain, combine the washing liquid and filtrate, concentrate to dry under reduced pressure, stir and dissolve with 10L deionized water, filter to take filtrate, add 0.5% activated carbon, heat at 70 ℃ for stirring, decolorize for 1h, filter to take filtrate, and let it cool to 0 ℃, add equal volume of diethyl ether for extraction, separate out of water layer, concentrate under reduced pressure to dry, add 10L of anhydrous ethanol for dehydration for 3 times, drain, add 2L of anhydrous ethanol to precipitate, stir evenly, add 10L of diethyl ether, cool to 0 ℃, filter to take precipitate, vacuum extract diethyl ether, and dry at 80 ℃ to obtain L-proline finished product. using gelatin as raw material, it is obtained by acid hydrolysis and ion exchange resin column chromatography.
toxic substance data	information provided by: pubchem.ncbi.nlm.nih.gov (external link)